/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.linkis.cs.optimize.dfs;

public class MinCostBinaryTree implements BinaryTree {

    Node rootNode;
    BinaryTree left;
    BinaryTree right;
    Double cost;

    public MinCostBinaryTree(Node rootNode) {
        this.rootNode = rootNode;
        if (this.rootNode.visited()) {
            return;
        }
        if (rootNode.getLeft() == null) {
            this.cost = rootNode.getCost();
            return;
        }
        if (rootNode.getRight() == null) {
            this.left = new MinCostBinaryTree(rootNode.getLeft());
            this.cost = this.left.getCost();
            return;
        }

        BinaryTree firstLeft = new MinCostBinaryTree(rootNode.getLeft());
        BinaryTree firstRight = new MinCostBinaryTree(rootNode.getRight());
        Double firstCost =
                firstLeft.getCost() * rootNode.getLeft().getPriority()
                        + firstRight.getCost() * rootNode.getRight().getPriority();

        rootNode.shift();

        BinaryTree secondLeft = new MinCostBinaryTree(rootNode.getLeft());
        BinaryTree secondRight = new MinCostBinaryTree(rootNode.getRight());
        Double secondCost =
                secondLeft.getCost() * rootNode.getLeft().getPriority()
                        + secondRight.getCost() * rootNode.getRight().getPriority();

        if (firstCost > secondCost) {
            this.left = secondLeft;
            this.right = secondRight;
            this.cost = secondCost;
        } else {
            rootNode.shift();
            this.left = firstLeft;
            this.right = secondRight;
            this.cost = firstCost;
        }
        this.rootNode.visit();
    }

    @Override
    public BinaryTree getLeft() {
        return this.left;
    }

    @Override
    public BinaryTree getRight() {
        return this.right;
    }

    @Override
    public Node getRootNode() {
        return this.rootNode;
    }

    @Override
    public Double getCost() {
        return this.cost;
    }
}
